Air system



July 21, 1931.

G. R. LAWRENCE AIR SYSTEM Filed April 23, 1926 6 Sheets-Sheet l A@ ATTORNEYS.

July 2l, 1931. l 5. R LAWRENCE AIR SYSTEM Filed April 23, 1926 6 Sheets-Sheet 5 BY ff/m' M 29g ATTORNEYS.

July 21, 1931. G. R. LAWRENCE AIR SYSTEM Filed April 23, 1926 6 Sheets-Sheet 4 July 2'1, 1931.

G. R. LAWRENCE AIR SYSTEM Filed April 2:5, 1926 6 Sheets-Sheet 5 I'nve'ntor GeoRLawrence Patented July 21, 1931 Nrr'en STATES `maar GEORGE B..v LAWRENCE, OF CHICAGO, ILLHWOIS, ASSIGNOR TO AIYAWIREN'I'JE DVELOP- KENT CO., OF DETROIT, MICHIGAN, A CORPORATION OFHICHIGAN AIB SYSTEM Application ait-.a apra a3,

.. The invention relates to air supplying systems.

@ne object of the invention is to provide an improved system forv supplying pure air of proper humidity to buildings and the like.

Another object of the invention is to provide an improved system for supplying air, in which provision is'made for automatically regulating the humidit of the air.

Another object of tl 'nvention is to provide an improved system which is adapted to be used either for supplying hot or cold air to buildings.

Another object of the' invention is to provide a simple and eiiicient air supply system which is adapted for installation in houses.

Another object of the invention is to provide an improved air supply system, in which provision is made for purifying the air by res moving particles of soot, products of coinbustion and the like from the air.

Another object of the invention is to provide an improved system in which the air is thoroughly washed and cleaned before it is delivered to the distributing duct for use.

Other objects ofvthe invention Willappeai l from the detail description.

rlhe invention consists in the several novel features hereinafter set forth and more particulaifiy defined by the claims .at the conclusion: hereof.

In the drawings: Fig. 1 is a vertical section through the washing apparatus and heater. Fig. 2 is a vertical section taken on line 2 2 of Fig. 1. Fig. 2a is a detail, illustrating the lower end of the distributing drum for rojecting water acrossv the path of the air. v ig. 9 is a plan of the heater, Washer and purifier. Fig. 3a is a section taken on line ila-3a of Fig. 2. Fig. 4 is a perspective, showing the system applied to a building. Fig. 4a is a perspective of a modification of a p ipe for delivering cooled air to the air purifying apparatus. Fig. 5 is a view partly in elevation and'partly in section of the humidity regulating instrument. Fig. 6 isla section taken on line 6--6 of Fig. 5. Fig. 6a is a section taken on line a--aof Fig. 5. Fig. 6b is a section on line (3b-6b of Fig. 5.

The invention is exemplified in a system 192e. serial No. 104,243.

which embodies an aii,` heater A which coinprises a. casing a; a. ire box a for any suitable fuel, usually gaseous fuel or oil; a serpentine air-duct a2, which is connected to receive air from trunk a", and extends back and forth in the upper portion of said casing and around the fire box; and an air outlet as, extending upwardly from the lower end of the duct a2 below the lire box to a delivery trunk 30. The products of combustion from the fire box a are conducted around the several loops of the duct a2 and transversely thereto and tcoutlets not shown which are connected to discharge into a chimney. The particular constructionof the heater shown is more fully set 'forth in an application filed by me Septemberv 16, 1925, Serial No. 56,759.

Trunk 30 is connected to any suitable num` ber of branches 31, to distribute the air tothe different. rooms or points Where the air is to be delivered. The invention also contemplates the distribution of unheated air through ducts 31 when cool air is desired, and for this purpose a valve 32 is pivoted so it can be swung into closed position, as shown' by dotted ylines in Fig. l, to close the heater duct a2, and a valve 34 which is pivoted so it may be swung into position to conduct air directly` from trunk a6 into the trunk 30 when'valve 32 is closed. This adapts the system for supplying air without passing it `through thevheater, when cool air is to be distributed.

Trunk a has an end which terminates at, and is connected to, a flexible tubular pipesection 10, which is connected to the .outlet l1 of a blower 12, which forces air through the trunk a, duct a2 and through the outlet a3 to the distributing ducts 31. The blower 12 is driven by an electric motor 13, which is mounted on top of the casing of the blower. The blower casing is mounted on the top of the casing B of an air washer, which is separate from the heater-casing a. This flexible' pipe section 1.0, between the blower andthe trunk a, prevents the vvibrations or noise, caused by the motor and blower, from being transmitted to the heater and their conduc` tion to the air-distributing system of the building.

vinto the lower portion of the. loop pipe Air inlet trunk f is connected to deliver air into the casing C of an air purifier, from which it passes through the washer to the blower 12. In practice, it is desirable to mix fresh air from the outside with the return air from the building into which the system discharges air, and for that purpose, trunk f is connected to receive air from a register f located at any convenient point, such as the floor of one of the rooms, and from a branch 2, which is extended to receive air from the outside of the building under control of a valve f3. A hinged door f4 is adapted to admit air to the trunk f from the basement of the building, when that is desired. Thisconstruction permits fresh air to be mixed with the return air in desired proportion, to keep the air in suitable condition for use in the building.

When the system is to beused for supplying coolair to the building, for example, in hot weather when the heater is not used, it is desirable to receive air from as cool a source as possible, and for this purpose a pipe G of suitable material of high thermal conductivity, such asfcopper, has one Aof its ends g connected to receive air from the basement. Pipe G has a vertical loop g2, which may be extended downwardly into the ground to a suiiicient depth where the ground is cool, so the temperature'of the air will be lowered materially by its passage therethrough. This pipe is preferably provided with longitudinal cooling fins g5. The other upper end of the loop is connected, as at g3, to deliver air into a duct g4, which is connected to discharge into .the inlet trunk f. A pump H is connected to an inlet pipe h which extnds so that the water condensate may be pumped out. To prevent restriction of the air supply, in event `that the cooling loop g? is of insufficient capacity or becomes clogged, a valve g7 i provided,` which is normally held closed by a weight g8, and is adapted to automatically open and admit air from the basement, if and when suction pressure in duct g* becomes excessive as the result of stoppage in pipe G. A hinged valve g, which is held closed hen the cooling pipe G is not used, may be swung into position shown by dotted lines in Fig. 2 to deliver cool air through duct g4 into trunk f. Air may also be advantageously drawn from this underground pipe in winter when the temperature overground is materially lower'than the underground Y temperature.- l

fIn lieu of extendinga loop of pipe vertically into the ground, it may be extended horizontally around the building and in the ground, as at G2 in Fig. 4a.

In practice, it-has been found that air in many places contains soot or other products of combustion and other impurities, and a` purier is illustrated which may, if desired,

A pan c2 at the bottom ofthe casing C contains a quantity of liquid, preferably a parne oil. An endless belt 03 of iine wire netting is of sufficient width to extend completely across the width of chamber c and extends around a roller c* which is submerged in the liquid or oil in pan 02, so that the traveling endless belt will receive a bath. From roller c4, both reaches of the belt extend obliquel u ward across the chamber o, and are guided tively. From said rollers, both reaches of the vbelt extend obliquely upward and reversely across the chamber toa drive-pulley o". As

Aa result of this arrangement, the air must pass through the belt four times in transit through the chamber o to' the inlet '01 of the casing. Pulley 09 is constantly driven by gearing comprising a worm 013 fixed to and driven by the shaft of motor 13; a worm gear c driven by said worm and fixed to a shaft el which is mounted in bearings on a-bracket c1 fixed tothe top of the casing of the electric motor 13; a sprocket-Wheel c, fixed to lshaft C15; a sprocket-wheel 019 fixed to one end of the shaft pulley 09 which projects from one side of thecasing; 'and a sprocket-chain 018 between sprockets c and o,

Brushes 02, 021 may be applied to the 0pposite faces of the reach of the belt passing away from the roller c, to wipe the excess o1l and any impurities adhering thereto from the belt. Roller c4 and said brushes are a air of rollers c o" res eo-` y 1 mounted in a frame 022 which is suitably mounted on one of the walls of the casing c, so that the roller and belt may be lifted out of the oil-bath to permit the pan 02 to be conveniently removed when the oil has become ldirty and it is desired to replace it with a fresh supply. This rame is held in` its lowered position by bolts 023 which may be loosened and tightened from the outside when the frame is to be raised or lowered, or the frame may be left loose so the weight of roller c* will act to keep thebel't taut.

In operation, the constantly travelling belt c3, in passing around roller c4, will be immersed in oil, and anyA excess of' oil will be wiped from it bv brushes 02, 021, so that the belt, in travelling back and forth across the chamber c will have thereon a film of oil, to which soot and other products or particles in the air will adhere. The air, entering the top of chamber c,`passes successively through the upper oppositely travelling'reaches of the belt and then through the oppositely peatedly pass through the belt in transit l through the casing to eliminate the particles in the air which have an aliinity for the liquid used on the screen. A characteristic of forcmg the air through the chamber, with line woven wire screeneXtending across it, is that every time the air laden with particles strikes against the upwardly'facing portions of the fine round wires forming the screen, `it will be dedected and divided thereby and then pass through the openings between the wires. rlhis causes the air, in passing through the meshes, to form eddies and low pressure areas adjacent the opposite or downwardly facing peripheral portions of the liquid coated wires. This will cause the fine particles in the air, which are not passing through the meshes, to adhere to the latter portions of the wires. Substantially all of the soot and other particles in the air will adhere to the liquid covered surfaces of the belt and eliminate them from the air before it leaves the casing C. rl`he belt will carry these products into the bath which will remove them from the belt. Any products, that will not be removed by their passage through the bath, will be wiped from the belt by brushes c2", c. From the chamber c, the air will pass out through inlet 01 to the chamber b and thence upwardly to the blower 12. A column of water is maintained in the lower portion of the casing. A pipe b2 delivers water to the casing under control of a valve b3 which is automatically operated by a float b4 to keep the water at a substantially predetermined level. An overflow pipe b5 is provided to carryo' any excess of water in event valve b3 fails to operate or when the washer is used to cool air, as hereinafter set forth. A deflector or splash plate 40 extends .around the sides of the chamber above the water column.. y

"A centrifugal drum b is secured tothe lower end of a shaft 56 which is connected to be driven by the shaft of the rotor 12, the drum being coaxial with the blower 12 and the motor 13, so that it may be directly driven without gearing. The drum b is in the general form of an inverted cone, and is adapted to project water in a very finely divided spray or mist, horizontally across the chamber b, through which the upwardly travelling air must pass in transit through the chamber b of the casing. This drum receives water into its lower end or apex through holes bs in a sleeve 68 which extends upwardly from the lower end of the drum and is attached to the shaft be". Sleeve 118 is rotatable around the tubular extension 14 of a fitting which has a flange 15 which is fixedly secured to the bottom of the casing. An opening 16, in sleeve 14. admits water to the ingress holes bs, the lower end of the drum being submerged for that purpose. A sleeve-valve 17 fits around the sleeve 14 and is provided with an openin 18 which is adapted to be brought into partia or complete registry with the opening 16 to regulate or control the admission of water from the column in the bottom of the casing to the drum b". A handle 19 is provided on the sleeve-valve 17, so it may be rotated. Water entering the reduced lower end of the rapidly rotating drum be will be subjected to centrifugal force which will distribute it throughout the area of the drum and force it up .irdly in the drum to fine perforations b9, through which the water will be discharged laterally by centrifugal force. The discharged water forms a substantially continuous spray or inist between the drum and the sides of the casing, to efficiently wash the air passing upwardly therethrough. The air after'passing through the centrifugal spray carries water upward in the form of a dense fog or mist above the drum. The water projected outwardly by the centrifugal drum and not carried upwardly with the air will drop into the column of water in the bottom of the casing. A delector 41 directs the air from inlet 01 under zone of centrifugal discharge, and prevents water from dripping into the chamber 0.

A fixed baile D made of fine wire screen extends across the chamber b above the centrifugal drum to eliminate the free water in the air. This screen is formed of very fine wire nettin and being constantly coated with water rom spray or mist serves to both continue to wash and collect free water. A

characteristic of forcing air through this baiile formed of fine woven wire screen is that the air being drawn upwardly by the blower 12 at considerable velocity strikes against the downwardly facing peripheral portions of the wire which will divide and deflect the air through the meshes or openings between the wires.` The air passing around the wires at this velocity will produce eddies adjacent the opposite or upwardly facing peripheral portions of the wires, and these eddies will cause the air passing around the wires to deposit the free water and liner impurities not already collected on the latter peripheral portions of the wires. This screen isbent into zigzag form as illustrated so as to to the lower apices of the angles of the screen and from there it will drop downwardly in the chamber b.

At times, it is desirable to additionally eliminate water from the air and to vary or regulate the humidity of the air passing to the blower. For this purpose, a pair of movable baffles D and D2 are provided to eliminate the free water which is carried upwardly by the air from the baille D. Each of the ballles D', D2 consists of a strip of wire netting (Z3 bent into zigzag form, similarly to the ballles D, to form a succession of portions connected by lower acute angles el, to operate similarly to the baille D. Each baille D',

2 is centrally fixed to a shaft d4, which extends across the upper portion lof the casing B, and is provided with a handle Z5 on the outside ofthe casing, so that each of these baflies may be turned to extend into operative position, as shown by full lines, or into inoperative position. Vhcn these bailies are positioned horizontally, they will be effective to arrest the free water in the air, and when turned into a vertical position, they will be substantially ineffective for that purpose. When these baffles are in their operative position, they will lessen the humidity of the air passing to the blower` and when in their inoperative position, the humidity of the air passing to the blower will not be lessened. These rotatable bailles exemplify means for varying the humidity of the air passing from the casing B In some instances, it is desired to additionally cool the air and to reduce its humidity, and for that purpose a coil of copper pipe E, consisting of several serially connected horizontally convoluted superposed coils e. is disposed in the casing B above the centrifugal drum and below the fix-ed baille D. The upper coil of this pi-pe is connected to receive water, usually of normal temperature, which is cooler than the air, through a pipe e from a box e, and the lower coil is extended, as at e2, to discharge the water into the centrifugal drum, from which it will be discharged by centrifugal force and projected laterally. Coils e act at all times -as baffles to eliminate -the free water between the baffles D and the centrifugal drum. Vhen the cool water is flowing through these co'ils, they will cool the upward current in chamber b, and the surplus humidity, caused bv lowering temperature of air employed,

will condense on the outside thereof. When the water is flowing through the cooling coils, the sleeve valve 17 may be closed, so that the water discharged from the coils will be projected across the chamber I) by the centrifugal drum b". If desired, water which has been chilled may be passed through the coils. When purified air is to be heated before distribution, the water is not passed from the coils e. If additional moisture or more water for washing` and cooling is desired` without humidity reduction. a-n `additional supply of water may be discharged directly into the centrifugal drum through a pipe b1 from the box e3. Water is supplied to said box through a pipe bm under control of a valve 517. A pivoted deflector b1 in said box is adapted to direct the water into drum 126, either through pipe 516, 0r through the pipe e', which delivers the water to the cooling pipe E. When an increase of water is desired for washing and cooling, without the humidity reduction produced by water flowing through the coils e, the deflector b1 is set to direct water into pipe bw. This exemplifies apparatus in the washing chamber for eliminating humidity and cooling air when desired, for controllably delivering water to the centrifugal drum, and in which the coils e assist in eliminating the free water from the air after it has passed across the centrifugally projected water.

In transit through the casing, the air will pass through or across the spray or mist which is forcibly projected laterally across the chamber. b by the centrifugal drum be. The upward current otl air produces a fog or mist above the drum and the coil-pipe E, and baille D will arrest the free water in the air before it reaches the blower 12 for distribution. If this baffling is insullicient, the

Vbaffles D and D2 are shifted into their op- The humidity of the air erative position. passing to the blower may be regulated by baflles D and D2. If it is desired to Acool the air, the deflector Z115 is set to direct cold Water into the pipe E, to cool the air in transit to the blower. The humidity reduction, caused by Water passing through coils e, may be controlled by se'lting the deflector b to direct Water directly into the drum bs, thereby increasing the humidity.

The invention provides for automatically and accurately controlling the humidity of the air delivered into the rooms by a regulator which controls the delivery of sullicient water into the washed air through a pipe m which discharges into the blower l2, to accurately make up any deficiency in moisture under varying conditions. The regulator comprises a suitable back or panel h which is adapted to be secured at any desired or convenient point to a wall in the room which is subject to temperature and humidity changes. The regulator also comprises thermally responsive elements K and K which are substantially parallel. Each of these elements is composed of strips having different co-eflicients of expansion. These strips are secured together in any manner well understood in the art, so that they will flex responsively to temperature changes. The lower end of the element K is secured at k2 to one side of a fixed U-shaped bracket h5, and the other element K is secured, at les, to the other side of said bracket. The elements extend vertically upward from said fixed bracket and are normally in substantially parallel relation. The upper ends of said elements are free to move laterally responsively to u their iiexure by temperature changes.

Therupper end of element K is pivoted at k to the vertical arm of a bell-crank lever k". The horizontal arm of said lever is pivoted at k1 to the Aupper end of a controller rod m9. The bell-crank lever is pivoted at k1" to one end of a stid cross-link lo?, the other end of which is pivoted at lo to the upper end of element K. This construction permits the lever lo to ulcrum, either at pivot 7c or pivot is, and permits the upper ends of the elements K, K to move di'erentially or relatively to each other in either direction. Any relative movement between the upper ends of said elements, as the result o the exure of either or both, causes the lever le" to be rocked about one'or the other of said fulcra. The rocking movement of this lever la is utilized to operate a controller rod m9 for a humidity-controlling instrumentality and also to operate a visual humidity-indicator.

To produce differential or relative movement between the elements K, K', responsively to humidity changes in the air around the regulator, and to correspondingly operate lever kg, element K is moistened by a wick 7cm, the lower free end of which is extended into a bodj, of water in a reservoir m, so that the wick will be4 kept wet, the

' evaporation of which will cool said element in proportion to the dryness of the air. The wick is lapped around one edge and the sides of the outer faces of element K and is suitably held thereon.

Reservoir m is formed in a base la* and is adapted to contain a column of water for delivery to an air system to regulate its humidity. W ater in receptacle m is kept at a substantially uniform level by means of a float m which is attached to an upwardly seating valve m2 which controls the ingress of water to the receptacle from a supply pipe ma. An

overfiow pipe m4 prevents an excess of water in said receptacle in event the float `fails to operate. The delivery of water from recep-` tacle m through a pipe Am5 to blower 12, to supply moisture to the air delivered by the system, is controlled by a valve m which is operated by controller rod m9 and is adapted to seat on the upper end of a nipple m7 which is screw-threaded to the bottom of the receptacle m. A handle m8 is fixed to the nipple m", so that the nipple, b turning it, may be adjusted relatively to t e valve m6 for the purpose of' maintaining relative humidity at a higher or lower percentage. Pipe m5 may be flexible', to permit the nipple to be turned c for this purpose.' Valve fm,6 is connected tol the lower end of rod m9 which is operatedl by lever les. Rod m exemplifies a controlling device for the valve me, to control the supply of water to regulate the humidity of the air. In some instances, it is desired to control a motor magnet or somek other suitable device for producing humidity. For this purpose, a member n is applied to the controller rod m9 to operate between adjustable switch or screw contacts n so that an electric circuit will be properly controlled by said rod. At the water line in the reservoir in base 7a4, rod m9 which'is formed of sections has a coupling 8O of low heat conductivity or of suitable non-expanding material, so the length of the rod will not be affected by the temperature of the water in said reservoir. A cover a of material of low thermal conductivity is provided for reservoir m to prevent the temperature of the water in said reservoir from influencing the elements K, K.

An indicator needle S is rigid with and extends downwardly from the horizontal arm of bell-crank lever lo. lts lower end is adapted to swing across a calibrated scale 82 adjacent a slot s" in a cover hs to give visual indications of the degree of humidity in the room where the regulator is placed responsively' gp control of lever k by the elements In response to temperature changes, the elements K, K will move differentially by reason of the cooling of the element K by -evaporation of the moisture in wick 7:12.

When the humidity is too low, the evaporation of moisture from wick k12 will be rapid,

which will cause the element-K to flex to the left, relatively to the element K. This relative movement of elements K, K will cause the lever 169 to discharge water responsively to the deficiency in the humidity of the room until the air has the desired humidity, whereupon the evaporation. of moisture will be retarded and element K will pass back to its normal position. When the temperature around the regulator is lowered, both of the elements K, K will flex to the left, according to the degree of temperature change, and when the temperature increases above .normal, both of the elements will flex to the right. At all times, the element K will be responsive to temperature changes with the element K and will be differentially responsive relatively to element K as the result of the influence of evaporation upon it, and lever k will always be operated responsively to this differ- (64 Fahr.) nine degrees difference between such bulbs gives fifty-six per cent humidity and six degrees higher temperature (76 Fahr.) eleven degrees difference in the bulb registration will give fifty-six per cent humidity. To compensate for these variations, the thermally responsive elements K, K are made of correct thickness and of such relative length that element K will liex relatively to element K one point for every six degrees of change in temperature. This relative shift of the elements will correspondingly rock the lever 7c to operate the controller rod m9 and correspondingly shift the valve m to vary the volume of water delivered through pipe m5 for humidifying the air in the proportions desired under different temperatures. Thus, this differential operation of elements K, K automatically compensates for the different proportions of moisture required to maintain the desired percentage of humidity at all teinperatures. The body movement of the lever k", resulting from the conjoint movement of the elements K, K responsively to temperature changes, moves the needle S to correct the reading on the scale s2 one point for every six degrees of changes of temperature.- As a result, the needle S provides a single visual indicator which will give the correct reading of the humidity under dili'erent temperatures in the room where the regulator is located.

A cover-plate 718 is provided to protect the front of the elements and the controller bar and has its lower margin fitted around the base h, so that it may be removed when access to the parts therein is desired. This cover is provided with openings 71.8 for circulation of air around the elements K, K.

For convenience in controlling the temperature of the air from the point at which the humidity is controlled, a thermostat, comprising. a thermally responsive element T, is associated with the regulator. Said element has its lower end fixed at t to the lower portion of an arm t which is pivoted at t2 to the panel h. The free end of element T is adapted to engage `contacts t3, t* which may be connected to control an electrical instrument for controlling the temperatures of the air in any suitable or well known manner. The arm t is manually operable by a in t which extends between pms t on the ower end of arm t and is fixed to a shaft t which is provided at its front end with an arm t8, the position of which is indicated by a scale t". By shifting arm t8, the neutral portion of element T may be changed to vary the temperatures at which the circuit through contacts t, t* will be closed.v A thermometer 'w is mounted on the front of the cover h. This humidity regulator exemplifies one which is controlled by a plurality of differentially voperating thermallyV responsive elements; also one in which'the humidity is'held at any desired percentage, regardless of temperature; also one in which provision is made for a visual indicator which is adapted to indicate the percentage of humidity under different temperatures.

rIhe operation of the improved air supply system will be as follows: When, as in cold weather, heated air is to be supplied to the rooms in the building, air valve 34 in the distributing trunk 30 will be closed and valve 32 will be set to direct air from the trunk a8 into the duct a2 of the heater A. Valve f3 in the intake f2 will be set to admit the desired portion of the air to the inlet trunk f, the remainder entering said, trunk f through the register 7c. At such time, the valve b" will be closed, so that no water will flow through the cooling pipe E in the washer. When the motor 13 is in operation, air will be drawn from the inlet trunk f downwardly through chamber c and through the several reaches of the travelling endless belt 03,*to remove the soot, other products of combustion and the like from the air. F rom chamber c, the air will be drawn by the blower 12 upwardly through the washer and into the casing of the blower. From the blower, the air will be discharged and forced through flexible pipe 10, trunk a, heater duct a2, outlet duct a3 and the distributing trunk 3() to the distributing branches 31, which will deliver it to the several places in the building where desired. In transit through the heater duct a2, the temperature of the air will be raised to the desired point, the humidity of the air will be accurately controlled to make up any deficiency in moisture under different temperatures by Ithe operation of the thermostatic regulator which variably controls-the delivery of water from the reservoir L to the blower casing, so that the heated air distributed will at all times be of proper humidity. In transit through the chamber b, the air will be thoroughly washed and the free water will be removed by the baflesbefore it enters the blower casing 12 for delivery in its passage to the heater and distributing line. By setting the ballles D", D2 into or out of operative position, the humidity of the air entering the blower may be varied to meet dii'e-rent conditions. If a greater volume of water is necessary, to eliect thorough washing of the air, than is fed into the drum from the water column in the bottom of chamber b. it may be supplied to the drum through the pipe -bm under control of the valve b and the lill) from contact with the cooling pipe E, so that humidity.

cold, purified, washed air will be discharged by the blower into the trunk as and thence into the distributing system. At times, the

Acooling will be suiiicient without water flowing through the cooling pipe E. The appa` ratus may also be used without drawing air from the underground loop g2, if desired. U ider all conditions, the thermostatic regulator H willl accurately control the humidity of the air delivered into the distributing ducts, so that it will be both clean and of the proper humidity.

The invention exemplifies an air supplysystem which is Well adapted for use 1n households, hot houses and other buildings. The apparatus is simple and can be produced at a, low cost. It is adapted to furnish, or circulate through a building, air which is clean at all times and of the proper The invention is not to be understood as restricted to the details set forth, since these may be modified within the scope of the appended claims, without departing from the spirit and scope of the invention.

Having thus described the invention, what I claim as new, and desire to secure by Letters Patent, is:

1. In an air supply system for buildings, the combination of .a distributing duct, a heater connected to discharge air to said duct, an airwasher embodying a driven element,

means for forcing air successively through the washer, the heater and said duct, and a motor for driving the air forcing means and washer.

2. In an air supply system for buildings, the combination of a distributing duct, a. heater connected to discharge air to said duct, an air-washer, comprising a driven element and a casing separate from the heater, means for forcing air successively through the washer, the heater andsaid duct, and a. l'notor for driving the air forcing Ymeans and washer,

mounted on the washer-casing.

3. In an air supply system for buildings, the combination of a distributing duct, a heater connected to discharge air to said duct, an air-washer comprising a driven kelement and a casing, an airuriner comprising a travelling belt, means or forcing air through the purifier, washer, heater and said duct, and a motor for driving the air forcing means and washer mounted on the casing.

4. In an air supply system for buildings,

4the combination of a distributing duct, a

heater connected to discharge air to said duct, an air washer comprlslng a caslng and a centrifugal projector, a blower for forcing air through the washer, the heater and said duct, a motor connected to drive the blower and projector mounted on the washer, and a co'nnection between the blower and the heater comprising a flexible pipe section to prevent sound con uction from the motor, blower and washer to the heater and the duct.

5. In an air supply system forbuildings, the combination of a distributing duct, an air-intake, a purifier comprisin an oiled element, for removing products rom the air, an air-washer, to which the airpasses from the purifier, and means for forcing air through the washer and said duct.

6. In an air supply system for buildings, the combination of a distributing duct, an airintake, a purifier comprising a travelling element having a liquid applied thereto for removing products from the air, an air-washer,

to which the air passes from the purifier, means for forcing the air through the washer and said duct, and a motor connected to drive said oiled element, the washerand said forcing means.

7. In an air supply system for buildings, the combination of a distributing duct, an air intake, a heater, a purifier comprising an oiled element for removing products from the air, an air-washer, to which the air passes from the purifier, and means for forcing the air through the element, washer, heater and said duct.

8. In an air supply system for buildings, the combination of a distributing duct, an airintake, a heater, a purifier comprising an oiled element for removing products from the air, an air-washer comprising a centrifugal drum to which the air passes from the purifier, a blower for forcing the air through the washer, heater, oiled element and said duct, and a motor connected to drive said oiled element, the blower and the drum.

9. In an air supply system for buildings, the combination of a distributing duct, an alrintake, a heater, an yair-washer comprising a casing and a centrifugal projector, a blower for forcing air through the' washer, heater and said duct mounted on said casing, and a motor supported on said casin and connected to drive said blower and sai projector.

10. In an air suppl system for buildings, the combination of a istributing duct, an air intake, a heater, an air purifier comprising a travelling screen, an air-washer com rising a casing and a centrifugal drum, a lower for forcing air through the washer, heater, screen and said duct, and a motor connected to drive said blower, drum and screen.

Signed at Chicago, Illinois, this 13th day of April, 1926.

' GEORGE R. LAWRENCE. 

